A blog from the Khan Academy Computing team. We'll post on what we've released, what we're working on, and what we learn as we go along.

Tuesday, October 1, 2013

Challenges: 56,000 completions in our first month!

“...this. is. AWESOME!!!!! I love you guys. This is so fun, I probably won't get any sleep tonight.”
- Dallas

In just our first month, just over 14,000 students have completed a Khan Academy coding challenge — nearly 56,000 challenge completions total! Overall, students completed 58% of the challenges they attempted, but over the last week, our completion rate jumped to 66%, likely thanks to improvements made based on user feedback.

We started with just a couple of challenges, but have steadily been adding more to make sure we assess every part of programming that we teach - like drawing, animation, and strings.

We really want students like Dallas to enjoy these challenges and to learn from them, so we’re gathering user feedback and aggregating statistics. We use the feedback that students send in to help us improve the challenges (like making the grader accept more variants of correct answers), and we look at the statistics to see overall trends in how students are doing in each of the challenges.

“My Favorite Foods” is the challenge with the highest completion rate (77%). It’s a simple challenge to use the text() command multiple times.

“Mickey Mouse Ears” is the challenge with the lowest completion rate (46%). It’s also the challenge that comes after a talk-through which many have said is too much of a jump from the last one - so that probably means we need both a talk-through and a challenge before those.

Going forward, we’ll continue to monitor both the aggregate stats and manual feedback to improve the challenges. Our goal is that every student that does actually understand a concept can get through the challenge of that concept, and that they aren’t blocked by confusing instructions or a bad grader. If we find that many students aren’t completing a challenge because they don’t understand a concept well enough, then we need to look at the curriculum (did we actually cover it well?) and also at the challenge ramp-up (do they need a simpler challenge to start off with?).